There was no need for Vince Cable to be so reserved. The government should not merely consider scrapping the second stage of Help to Buy, as the business secretary advised. It should do so immediately.

State subsidies for mortgages, either as cheap 20% loans on newbuild homes (stage one) or as insurance for mortgage lenders (stage two), was a terrible idea when George Osborne announcedit in March. As many economists pointed out, house prices never collapsed in the UK; and affordability, as measured by house prices-to-earnings ratios, remained stretched. The chancellor might succeed in "making the aspiration of home ownership a reality" for some but only at the cost of pushing house prices further beyond the reach of the next generation of first-time buyers. Young people would be driven deeper into "indentured servitude," as one City analyst memorably put it.

The thin counter-argument that the housing market needed a kick-start, if only to encourage housebuilders to build more homes, has surely been undermined by events since March. House prices recorded the fastest rise in seven years last month, according to the Royal Institution of Chartered Surveyors' survey this week. Meanwhile, the availability and price of mortgages is vastly improved, much helped by the Bank of England's Funding for Lending scheme.

Witness the rocket that has been put under housebuilders' businesses. Barratt Developments yesterday announced a 74% rise in annual profits to £192m, said completion volumes were up by more than a fifth over two years and reported that "the housing market recovery [is] starting to spread beyond London and the south east."

Add it all up and it should be clear that more artificial fuel is not required at this point. The housing market certainly does not need a scheme that will be in place for a full three years, which is the Treasury's current intention.

Even the boss of Barclays -- who, one might assume, would welcome the chance to have the state guarantee a 15% slice of mortgages on house purchases worth up to £600,000 -- sounds worried. Chief executive Antony Jenkins said this week: "We are seeing probably a more buoyant housing market for the first time in perhaps as much as a decade. That's a bit concerning because there is the risk of a property-driven boom in the UK. The regulators are on it and don't intend to let it happen but these things can be difficult to control."

Yes, you bet, they can be difficult. A chief difficulty is that expectations of inflation can become unhinged. That would make it harder for the Bank of England to deliver the low interest rates that it believes may be required for years, especially in the productive areas of the economy.

Mark Carney's answer to that conundrum is that we should keep the moves in the housing market "in some perspective," as he put it in Nottingham the other week. "Mortgage approvals themselves are currently running at a little more than half, and transactions a little more than two-thirds, of their pre-crisis levels," said the Bank governor. The "important thing to recognise," he added, is the Bank has new tools to contain risks in the property and financial sectors. It can, for example, make recommendations to banks and building societies to tighten lending terms or even raise capital requirements on mortgages.

Hold on a minute, though. If we're searching for perspective, the broad point to remember is that Help to Buy was presented as an emergency measure. Six months later, the picture looks different. According to the chancellor, the economy has turned a corner. So why proceed with a policy that could have the very dangerous side-effect of encouraging borrowers to take on large sums of debt just as the City (if not Carney) is talking about a rise in interest rates next year?

And is it really reassuring that the Bank has the powers to act to cool the housing market? It would be better if Osborne secured in advance a mandate from the Bank's financial policy committee (FPC), in charge of policing risks, that it is wise to proceed with stage two in January. That is what the Treasury select committee advised in April when it called on the government to get a second opinion. On Osborne's plan, the FPC only gets a veto in 2017 on any extension to Help to Buy. Come on, three years is an age in the bubble-prone UK housing market.

There ought to be an easy political get-out here for the chancellor. He could argue that, in light of positive economic developments, the taxpayer no longer needs to get into the strange game of underwriting mortgages on £600,000 homes. He could present the U-turn as a welcome return to normality, rather like his upcoming sale of shares in Lloyds Banking Group. He should take the opportunity now.